Writing instrument, more particularly a ball-point pen



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WRITING INSTRUMENT, MORE PARTICULARLY A BALL-POINT PEN Feb. 6, 1962 2 Sheets-Sheet 1 Filed Jan. 4, 1960 H AMBROS Feb. 6, 1962 WRITING INSTRUMENT, MORE PARTICULARLY A BALL-POINT PEN 2 Sheets-Sheet 2 Filed Jan. 4, 1960 INi ENTOR. jiAlzz/broa United States The present invention relates to a writing instrument, and more particularly to a ball-point pen having a writing cartridge which is axially supported in a barrel and with abutment means which is indirectly or directly urged by a return spring into a notch of a non-rotatable shifting sleeve which comprises one or more shallow notches.

for the writing position and one or more deep notches for the inoperative position, the change from one notch to another being accomplished by depressing a push button which projects from the end of the barrel and acts on the writing cartridge.

In known types of writing instruments a lug abuts during the shifting from one notch to another against oblique surfaces provided on the shifting sleeve, whereby the lug carrier is rotated in relation to the shifting sleeve. After some time the oblique surfaces become worn which soon causes trouble in the use of the writing instrument.

It is therefore an object of the present invention to provide a shifting mechanism in which the oblique surfaces of the shifting sleeve notches are practically relieved of any loads during the shifting operation. According to the invention this is achieved by supporting in the shifting sleeve a nut which is axially movable and rotatable and which comprises the abutment or lug, a spindle adapted to be axially displaced by means of the push button projecting through said nut in such a manner that the nut by means of a spring is urged on the spindle into the next shifting position as soon as the lug has left the notch in which it has been engaged.

Further objects and features of the invention will become apparent from the following description taken in connection with the accompanying drawings in which two embodiments of the invention are illustrated by Way of example only. In the drawings:

FIG. 1 is a longitudinal sectional view of a ball-point pen according to the invention, with the parts thereof in the inoperative position;

FIG. 2 shows the ball-point pen illustrated in FIG. 1, partly in longitudinal section and with the parts thereof in another position;

FIG. 3 is another partial longitudinal section of the writing instrument shown in FIG. 1, in still another position and FIG. 4 is a longitudinal sectional view of another ballpoint pen embodying the invention.

The ball-point pen shown in FIGS. 1 to 3 of the drawings comprises a hollow barrel 1 into the rear end of which is screwed a sleeve 2 which is provided with a bottom 3 and encloses the shifting mechanism. The sleeve 2 is firmly closed by a cap 4 the inwardly directed portion of which is formed as a shifting sleeve by providing the edge thereof with two shallow notches 6 (FIG. 3) and two deep notches 7 (FIG. 2) which are arranged in alternating sequence. Axially slidable and rotatably supported in the shifting sleeve is a nut 8 which may be made of plastic material and on the periphery thereof is provided with diametrally opposite abutment lugs or ledges 9 which are urged into the notches 6 or 7 by a spring 10 bearing against the bottom 3 and on the nut 8.

The nut 8 is internally threaded with a coarse pitch thread and is traversed by a spindle 11 which has a similar mating coarse pitch thread, the rear end of the atent ice spindle being rigidly secured in a push button 12 which projects through the cap 4. The thread of spindle 11 is somewhat longer than the nut 3 so that the nut moving on the spindle will make. a part of a revolution as it moves from one end'of the spindle to the other. The front end of the spindle 11 carries an end disk 13 and bears against the end of a Writing cartridge 14 which is subject to the action of a return spring 15 and is slidably guided in the barrel 1. The rear end of the writing cartridge projects througha central bore in the bottom member 3 into contact with the bottom end of spindle 11 at disc 13.

FIG. 1 shows the ball-point pen in the inoperative position with the writing cartridge retracted. In order to move the writing cartridge 14 forward into the writing position, the push button 12 is depressed, generally with the thumb. Thefriction between thumb and push button 12 thereby prevents rotation of the button and of the spindle. The nut is prevented from rotating by lug 9 bearing against the side of notch 7. Push button 12, spindle 11, nut '8 and writing cartridge 14, therefore move forward without rotation while the springs 10 and 15 are compressed.

FIG. 2 illustrates this operation during which the lugs 9 of which only one may be seen, move out of the deep notches 7. The drawing shows the parts of the writing instrument in the position which they occupy shortly before the lug 9 leaves the deep notch 7. As soon as the lug 9 is released from the deep notch 7 by further depression of the push button 12, the nut 8 will be rotated on the spindle 11 to the right in FIG. 2, under the effect of the spring 10 that forces the nut S upward on spindle 11. Because the nut 8 is now free of the restraint of lug 9 bearing on the side of notch 7, nut 8 rotates a part turn and stops, as seen in FIG. 3, with the top of nut 8 against the bottom of push button 12. By means of this drive movement of the spindle, the nut 8 is brought into position so that upon release of push button 12 the lug 9 engages in the shallow notch 6 thereby limiting the return movement of the writing cartridge 14. The writing point of the cartridge then is held projecting from the forward end of the barrel 1 and thus assumes the writing position. The spindle 11, when push button 12 is released, is pressed upwardly by cartridge 14. Nut 8 can only move up until stopped by notch 6. Spindle 11, however, continues to move upwardly and will rotate in nut 8 to again move push button 12 upwardly to project full length from the top of cap 4.

The device then is in position similar to that of FIG- URE 1 so that when the push button 12 is again depressed, the operation just described is repeated. The

lugs 9 of the nut 8 are shifted to the next notch which is a deep notch 7. The writing instrument has then again assumed the position shown in FIG. 1.

The embodiment illustrated in FIG. 4 differs from that shown in FIGS. 1 to 3 insofar as a spindle 11 is not rigidly but loosely mounted in the push button 16. The nut 17 which is provided with short lugs 9' abuts against a clamping sleeve 18 which through the intermediary of a return spring 19 bears against the bottom 3' of sleeve 2'. A Writing cartridge 20 is removably mounted in the clamping sleeve 18 so that it can readily be exchanged.

The operation of the instrument shown in FIG. 4 is substantially the same as that of the other embodiment shown in FIGS. 1 to 3 with the difference, however, that the spindle 11' does not rotate With the push button '16, but the spindle 11' can rotate together with the writing cartridge 20. The elements in FIG. 4 that are similar to the elements in FIGS. 1, 2 and 3 are designated by the same reference characters raised to prime. Spring 5 19 is the equivalent of spring 15 of FIGS. 1-3 and spring 17 is the equivalent of spring 10 of FIGS. 1-3.

What is claimed is:

1. In a mechanical Writing device or the like of the type having a hollow barrel, 2. writing cartridge having a writing point positioned axially of said cartridge and axially movable therein to be positioned with its Writing point in an extended operative position or in a retracted inoperative position, the improvement comprising a nut axially and rotatably mounted in the end of said barrel remote from said writing point, at least one axially extending lug on the outer surface of said nut, a cap on said barrel adjacent said nut, a shifting sleeve on said cap engageable by said lug, said shifting sleeve being provided with at least one shallow and one deep notch into which said lug may penetrate when moved axially toward said shifting sleeve to position said writing cartridge in extended or retracted position, respectively, a threaded spindle threaded within said nut, the pitch of threads of said spindle and nut being so great as to normally rotate said nut upon axial movement of said spindle, said shallow and said deep notches normally holding said nut against rotation, whereby upon axial movement of said threaded spindle said nut will be moved axially to a position clear of said notches whereupon said nut will be rotated, means on said spindle engaging said cartridge whereby the axial position of said cartridge is determined by the axial position of said spindle, means extending through said cap for digital manipulation whereby said spindle may be urged toward said writing point, and a spring biasing said nut toward said cap to rotate said nut from one said notch to the other when clear of said notches.

2. The device of claim 1, in which said spindle is provided with a clamping sleeve to hold said writing cartridge.

3. The device of claim 1, in which said cartridge is spring biased toward said spindle.

4. A writing instrument characterized by a combination or" a barrel assembly, a spring loaded cartridge Within said barrel assembly in axial slidable arrangement therewith between an inoperative position with the cartridge retracted within the barrel and a projected writing position with the point of the cartridge exposed through the barrel, the rear end portion of said barrel assembly having shallow and deep notches arranged therein in alternating sequence, a threaded nut within the barrel assembly adjacent said portion, abutment means on said nut receivable in said notches to define the writing and inoperative positions, respectively, of said cartridge, an actuating spring within said barrel adapted to press said abutment means against said notches, a threaded spindle axial y projecting into said nut, the threads of said spindle and nut operating to rotate said spindle and nut relative to each other upon relative axial movement therebetween, and a push button arranged in said barrel assembly and in axial alignment with said spindle for moving said spindle axially in a direction to move said abutment means from said notches, said spindle pressing on said cartridge and having a longer axial extent than said nut whereby axial movement of said push button and spindle removes the abutment means for the notches so that the actuating spring may then rotate the nut on the spindle for positioning said abutment means in the succeeding notch.

5. The writing instrument of claim 4, in which a sleeve is fixed across the barrel assembly, one end of said actuating spring resting upon said sleeve.

References Cited in the file of this patent FOREIGN PATENTS 

